Removable trackball for a handheld wireless communication device

ABSTRACT

A handheld wireless communication device cradleable by an user during text entry. A display and key field are located on a front face of the device. The key field includes alphanumeric input keys and menu control keys. Additionally, an user-removable trackball navigation tool is provided on the device. The trackball navigation tool can be releasably snap-engaged or releasably friction-engaged in the body of the device. The removable trackball navigation tool enables the user to independently remove the trackball navigation tool from the device and perform self-maintenance on the device with respect to the navigation tool.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a non-provisional of and claims the benefitof U.S. Provisional Application No. 60/767,231, filed Mar. 13, 2006.Said application is hereby expressly incorporated herein by reference inits entirety.

FIELD

The present disclosure, in a broad sense, is directed toward handheldelectronic devices. More specifically, the disclosure is directed towardhandheld communication devices that have wireless communicationcapabilities and the networks within which the wireless communicationdevices operate. The present disclosure further relates to the mountingof the trackball assembly on the handheld communication device.

BACKGROUND

With the advent of more robust wireless communications systems,compatible handheld communication devices are becoming more prevalent,as well as advanced. Where in the past such handheld communicationdevices typically accommodated either voice transmission (cell phones)or text transmission (pagers and PDAs), today's consumer often demands acombination device capable of performing both types of transmissions,including even sending and receiving e-mail. Furthermore, thesehigher-performance devices can also be capable of sending and receivingother types of data including that which allows the viewing and use ofInternet websites. These higher level functionalities necessarilyrequire greater user interaction with the devices through included userinterfaces (Uls) which may have originally been designed to accommodatemaking and receiving telephone calls and sending messages over a relatedShort Messaging Service (SMS). As might be expected, suppliers of suchmobile communication devices and the related service providers areanxious to meet these customer requirements, but the demands of thesemore advanced functionalities have in many circumstances rendered thetraditional user interfaces unsatisfactory, a situation that has causeddesigners to have to improve the Uls through which users inputinformation and control these sophisticated operations.

Keyboards are used on many handheld devices, including telephones andmobile communication devices. The size of keyboards has been reducedover the years, as newer, smaller devices have become popular. Cellphones, for example, are now sized to fit in one's pocket or the palm ofthe hand. As the size of the devices has decreased, the more importantit has become to utilize all of the keyboard surface as efficiently aspossible.

Many keyboards on mobile devices have an input device for navigationthrough the graphical user interface. These interfaces include suchdevices as trackballs and rotating wheels which can be used to affectmovement of a cursor or pointer, or to scroll up, down and about adisplayed page. These navigation devices often occupy a relatively largeamount of space on the incorporating mobile device. Because thenavigation device is frequently used and often requires fine control, alower end size limitation will normally be observed by device designers.To accommodate such larger, more convenient navigation devices on thehousing of the mobile device, the amount of space that is available forthe keys of the keyboard is correspondingly reduced if the keyboard andnavigational device are proximately located to one another.

Frequent use of an input device such as a trackball may make thetrackball and its corresponding trackball assembly susceptible to randomdebris or particulate contamination. Such contamination can interferewith the rotation motion or navigation of the input device.Additionally, trackball input devices on handheld electronic devices mayoccasionally experience functional failures where the trackball and/ortrackball assembly may require repair or replacement. For example,failures due to possible defects in manufacturing, failures caused bymechanical shock from being dropped by the user, any other impropermisuse of the handheld electronic device or the like could prevent thetrackball assembly from functioning properly. Thus, a handheldelectronic device that facilitates the removal of the trackball assemblyis desired.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary methods and arrangements conducted and configured according tothe advantageous solutions presented herein are depicted in theaccompanying drawings wherein:

FIG. 1 depicts a handheld communication device configured according tothe present teachings cradled in the palm of a user's hand;

FIG. 2 is a block diagram representing a wireless handheld communicationdevice interacting in a communication network;

FIG. 3 is a detail view of the support frame with the trackball assemblymounted thereon;

FIG. 4 is an exploded view of the retaining clips, trackball assemblyand support frame;

FIG. 5 a illustrates an exemplary QWERTY keyboard layout;

FIG. 5 b illustrates an exemplary QWERTZ keyboard layout;

FIG. 5 c illustrates an exemplary AZERTY keyboard layout;

FIG. 5 d illustrates an exemplary Dvorak keyboard layout;

FIG. 6 illustrates a QWERTY keyboard layout paired with a traditionalten-key keyboard;

FIG. 7 illustrates ten digits comprising the numerals 0-9 arranged in atraditional, ITU Standard E.161 numeric telephone keypad layout,including the * and # flanking the zero;

FIG. 8 illustrates a traditional or standard phone key arrangement orlayout according to the ITU Standard E.161 including both numerals andletters;

FIG. 9 is a perspective view of another exemplary handheld communicationdevice cradled in a user's hand and displaying an array of four icons(1, 2, 3 and 4) on a display thereof,

FIG. 10 is a schematic representation of an auxiliary user input in theform of a trackball; and

FIG. 11 is an exploded perspective view of an exemplary wirelesshandheld electronic device incorporating a trackball assembly as theauxiliary user input.

DETAILED DESCRIPTION

An exemplary handheld electronic device 300 such as is shown in FIG. 1and the device's cooperation in a wireless network 319 is exemplified inthe block diagram of FIG. 2. These figures are exemplary only, and thosepersons skilled in the art will appreciate the additional elements andmodifications necessary to make the device 300 work in particularnetwork environments.

The block diagram of FIG. 2 denotes the device's 300 inclusion of amicroprocessor 338 that controls the operation of the device 300. Acommunication subsystem 311 performs all communication transmission andreception with the wireless network 319. The microprocessor 338 furtherconnects with an auxiliary input/output (I/O) subsystem 328, a serialport (preferably a Universal Serial Bus port) 330, a display 322, akeyboard 332, a speaker 334, a microphone 336, random access memory(RAM) 326, and flash memory 324. Other communication subsystems 340 andother device subsystems 342 are generally indicated as beingfunctionally connected with the microprocessor 338 as well. An exampleof a communication subsystem 340 is that of a short range communicationsystem such as BLUETOOTH® communication module or an infrared device andassociated circuits and components. Additionally, the microprocessor 338is able to perform operating system 408 functions and preferably enablesexecution of software applications on the communication device 300.

The included auxiliary I/O subsystem 328 can take the form of a varietyof different navigation tools including a trackball 321 based device, athumbwheel, a navigation pad, or a joystick, just as examples. Thesenavigation tools are preferably located on the front surface of thedevice 300 but may be located on any exterior surface of the device 300.Other auxiliary I/O devices can include external display devices andexternally connected keyboards (not shown). While the above exampleshave been provided in relation to the auxiliary I/O subsystem 328, othersubsystems capable of providing input or receiving output from thehandheld electronic device 300 are considered within the scope of thisdisclosure. Additionally, other keys may be placed along the side of thedevice 300 to function as escape keys, volume control keys, scrollingkeys, power switches, or user programmable keys, and may likewise beprogrammed accordingly.

As may be appreciated from FIG. 1, the handheld communication device 300comprises a lighted display 322 located above a keyboard 332 suitablefor accommodating textual input to the handheld communication device 300when in an operable configuration. The front face of the device has akeyfield 650 that includes menu keys 652, alphanumeric keys 630,alphabetic keys 632, numeric keys 42, and other function keys as shownin FIG. 1. As shown, the device 300 is of unibody construction, alsoknown as a “candy-bar” design.

Keys, typically of a push-button or push-pad nature, perform well asdata entry devices but present problems to the user when they must alsobe used to affect navigational control over a screen-cursor. In order tosolve this problem the present handheld electronic device 300 preferablyincludes an auxiliary input 328 that acts as a cursor navigational tooland which is also exteriorly located upon the front face of the device300. Its front face location is particularly advantageous because itmakes the tool easily thumb-actuable like the keys of the keyboard. Aparticularly usable embodiment provides the navigational tool in theform of a trackball 321 which is easily utilized to instructtwo-dimensional screen cursor movement in substantially any direction,as well as act as an actuator when the ball 321 is depressed like abutton. The placement of the trackball 321 is preferably above thekeyboard 332 and below the display screen 322; here, it avoidsinterference during keyboarding and does not block the user's view ofthe display screen 322 during use.

FIG. 3 depicts incorporation of a trackball navigation tool or assembly328, trackball 321, and outer locking ring 23 in a support frame 11 of ahandheld mobile communication device 300.

As shown in FIG. 4, a removable trackball assembly 328 provides severalcharacteristics which lend themselves to easier and more effectiveservicing or replacement on a support frame 11 of a handheld electronicdevice 300. The trackball 321 is supported by the trackball assembly 328and rotates freely. Its spherical shape allows the trackball 321 torotate in any desired direction. The trackball assembly 328 includes asensor assembly that detects the motion of the ball 321 and is explainedin detail below. The trackball assembly 328 is locked into positionwithin a cavity well 50 in the handheld mobile communication device 300.The cavity 50 is positioned between the display screen 322 and thedevice keypad 332, and is substantially cylindrical in shape. Othercavity orientations can also be utilized. The cavity 50 includes aplurality of retention clips 58 that in conjunction with an innerlocking ring 22 and an outer locking ring 23 are used to affix thetrackball assembly 328 to the device 300 in a secure fashion. Thelocking rings are color coded with respect to each other in order toencourage proper placement and orientation with respect to the trackball321 and the assembly 328.

In other embodiments, the inner locking ring 22 can be described as aball retaining clip. This ball retaining clip comprises a ball retainingring 51 and a plurality of fixing feet 54 extending from the ballretaining ring 51. Each of the plurality of fixing feet extends in adirection parallel to the longitudinal axis of the trackball assembly328. The longitudinal axis as described herein refers to the assemblyline 59 shown in FIG. 4. Likewise, the outer locking ring 23 can bedescribed as trackball assembly retaining clip for releasably retainingthe trackball assembly 328 in the cavity 50. The trackball assembly clipcomprises a trackball assembly retaining ring 53 and a plurality ofsnap-engaging feet 56 extending from the trackball assembly retainingring 53. Furthermore, each of the plurality of snap-engaging feetextends in a direction parallel to the longitudinal axis of thetrackball navigation tool 328.

The trackball assembly 328 is held in place by the outer locking ring 23and a plurality of retention clips 58 contained within the cavity well50. Retention clips 58 are made from generally lightweight material thatis substantially rigid, but flexible enough to permit the requiredsnap-actions. The inner locking ring 22 holds the trackball 321 inplace, but allows rotation of the ball 321. The lock ring 22 alsopermits the trackball 321 to be removed from the incorporating device300 for replacement or servicing. Furthermore, the trackball 321 rotatesabout a plurality of axes that includes a first and second axis ofrotation and which enables full freedom of rotation of the trackball321.

Outer locking ring 23 further comprises a plurality of snap-engagingfeet 56 extending laterally along the lower edge of the ring 23 relativeto the cavity 50. The lower portion of the snap-engaging feet 56releasably clip into retention clips 58 to secure the trackball assembly328 in place.

The inner locking ring 22, in conjunction with the retaining clips andthe cavity well 50, affixes the trackball assembly 328 to the frame 11of the handheld device 300. Furthermore, the disassembly of theaforementioned components allows the removal of the assembly unit 328for maintenance or replacement. The inner locking ring 22 restricts theassembly unit's coplanar movement with the cavity well 50. The innerlocking ring 22 also comprises a plurality of fixing feet 54 extendinglaterally along with the lower edge of the inner locking ring 22relative to the cavity 50. The lower portion of the inner locking ring22 further comprises fixing feet 54 in order to secure it to theassembly 328. The retention clips 58 of the cavity well 50 engage theassembly unit 328 thereby affixing the unit 328 within the cavity well50.

Additionally, the trackball assembly 328 has a plurality of lateralports 57 extending around the outer wall of the assembly 328. Theseports 57 are parallel to the cavity retention clips 58 and allow theclips 58 to be placed within the ports 57 in order to facilitate lockingthe assembly unit 328 into the cavity well 50. The top portion of thecavity retention clips 58 generally comprises substantially flattenededges. The flattened top portions of the retention clips 58 are slightlyangled downward relative to the body of the handheld device 300 in orderto provide additional retention force for the assembly unit 328 eitherthrough added friction or snap engagement with the lateral ports 57.

The arrangement is such that removal of the assembly 328 is allowed onlywhen the clips 58 are removed from engaging the lateral ports 57 of theassembly 328. Furthermore, the snap-engaging feet 56 can be designed toreleasably engage a lateral port 57 in the cavity 50 at the front face370 of the body. Thus, removal of assembly 328 would further requiredisengaging these snap-engaging feet 56 from the lateral port 57.

To remove the assembly unit 328 from the cavity well 50, force isapplied to the clips 58 so that the clips 58 no longer frictionallyengage or snap engage the assembly housing. This applied force will alsodisplace the clips 58 from their coupling in the ports 57 of theassembly unit 328. Once the engagement of the clips 58 is eliminated,the assembly can be removed by axially sliding the assembly 328 out ofthe cavity 50.

Referring again to FIG. 1, the handheld wireless communication device300 is also configured to send and receive voice communications such asmobile telephone calls. At least one key of the key field 650 ispositioned adjacent to the trackball navigation tool and that key has acircular arc-shaped edge conformance fitting to a circular arc-shapedboundary about the trackball navigation tool 328. To facilitatetelephone calls, two call keys 605, 609 oppositely and laterally flankthe trackball navigation tool. One of the two call keys is a callinitiation key 605 and the other is a call termination key 609.

The key 606 positioned adjacent to the trackball navigation tool 328 isa menu key that upon actuation displays an available action menu on thedisplay in dependence of the currently running application on the device300.

The trackball navigation tool 321 enables methods and arrangements forfacilitating diagonal cursor movement in such environments as iconarrays 70 and spreadsheet grids on a display screen 322 of a relativelysmall, wireless handheld communication device 300, variously configuredas described above, such as that depicted in FIG. 9. One exemplaryembodiment takes the form of a method for affecting movement of a cursor71 on the display screen 322 of a handheld communication device 300. Themethod includes sensing movement at an auxiliary user input 328 of thehandheld communication device 300 indicative of the user's desire toaffect diagonal movement of the cursor 71 on the display screen 322 ofthe handheld communication device 300. X-direction signals andy-direction signals are produced based on the sensed movement at theauxiliary user input 328. During that time while the necessary signalsare being collected and processed, the cursor 71 is held steady on thedisplay screen 322 until a predetermined criterion is met fordiscriminating whether the user has indicated x-direction cursormovement, y-direction cursor movement or diagonal cursor movement. Inthat the processing is typically conducted by a processor 338 accordingto a resident computer program, the predetermined criterion is either apreset condition or a user definable condition.

The apparatus of a handheld communication device 300 is disclosed thatis capable of affecting diagonal movement of a highlighting cursor 71amongst an array of icons 70 on a display screen 322 of the handheldcommunication device 300. The display screen 322 is located above akeyboard 332 suitable for accommodating textual input to the handheldcommunication device 300 and an auxiliary user input 328 is locatedessentially between the display 322 and keyboard 332. Sensors 72, 78(74, 76) are provided that are capable of sensing movement at theauxiliary user input 328 indicative of the user's desire to affectdiagonal movement of the highlighting cursor 71 from a currentlyhighlighted icon number 73 on the display screen 322 to a diagonallylocated icon 75 on the display screen 322 of the handheld communicationdevice 300. The sensors produce x-direction signals and y-directionsignals based on the sensed movement at the auxiliary user input 328. Aprocessor 338 is included that is capable of analyzing the producedx-direction signals and y-direction signals and outputting a cursorcontrol signal that holds the highlighting cursor 71 steady on apresently highlighted icon 73 on the display screen 322 during theprocessing and until a predetermined criterion is met for discriminatingwhether the user has indicated movement to an icon left or right of thepresently highlighted icon, above or below the presently highlightedicon 73, or diagonally positioned relative to the presently highlightedicon numeral 73 and then affecting diagonal movement of the highlightingcursor number 71 between diagonally positioned icons on the displayscreen of the handheld communication device 300 when diagonal cursormovement is discriminated to have been user indicated.

Furthermore, the device is equipped with components to enable operationof various programs, as shown in FIG. 2. In an exemplary embodiment, theflash memory 324 is enabled to provide a storage location for theoperating system 408, device programs 358, and data. The operatingsystem 408 is generally configured to manage other application programs358 that are also stored in memory 324 and executable on the processor338. The operating system 408 honors requests for services made byapplication programs 358 through predefined application program 358interfaces. More specifically, the operating system 408 typicallydetermines the order in which multiple applications 358 executed on theprocessor 338 and the execution time allotted for each application 358,manages the sharing of memory 324 among multiple applications 358,handles input and output to and from other device subsystems 342, and soon. In addition, users can typically interact directly with theoperating system 408 through a user interface usually including thekeyboard 332 and display screen 322. While the operating system 408 in apreferred embodiment is stored in flash memory 324, the operating system408 in other embodiments is stored in read-only memory (ROM) or similarstorage element (not shown). As those skilled in the art willappreciate, the operating system 408, device application 358 or partsthereof may be loaded in RAM 326 or other volatile memory.

In a preferred embodiment, the flash memory 324 containsprograms/applications 358 for execution on the device 300 including anaddress book 352, a personal information manager (PIM) 354, and thedevice state 350. Furthermore, programs 358 and other information 356including data can be segregated upon storage in the flash memory 324 ofthe device 300.

When the device 300 is enabled for two-way communication within thewireless communication network 319, it can send and receive signals froma mobile communication service. Examples of communication systemsenabled for two-way communication include, but are not limited to, theGPRS (General Packet Radio Service) network, the UMTS (Universal MobileTelecommunication Service) network, the EDGE (Enhanced Data for GlobalEvolution) network, and the CDMA (Code Division Multiple Access) networkand those networks, generally described as packet-switched, narrowband,data-only technologies which are mainly used for short burst wirelessdata transfer. For the systems listed above, the communication device300 must be properly enabled to transmit and receive signals from thecommunication network 319. Other systems may not require suchidentifying information. GPRS, UMTS, and EDGE require the use of a SIM(Subscriber Identity Module) in order to allow communication with thecommunication network 319. Likewise, most CDMA systems require the useof a RUIM (Removable Identity Module) in order to communicate with theCDMA network. The RUIM and SIM card can be used in multiple differentcommunication devices 300. The communication device 300 may be able tooperate some features without a SIM/RUIM card, but it will not be ableto communicate with the network 319. A SIM/RUIM interface 344 locatedwithin the device 300 allows for removal or insertion of a SIM/RUIM card(not shown). The SIM/RUIM card features memory and holds keyconfigurations 351, and other information 353 such as identification andsubscriber related information. With a properly enabled communicationdevice 300, two-way communication between the communication device 300and communication network 319 is possible.

If the communication device 300 is enabled as described above or thecommunication network 319 does not require such enablement, the two-waycommunication enabled device 300 is able to both transmit and receiveinformation from the communication network 319. The transfer ofcommunication can be from the device 300 or to the device 300. In orderto communicate with the communication network 319, the device 300 in apreferred embodiment is equipped with an integral or internal antenna318 for transmitting signals to the communication network 319. Likewisethe communication device 300 in the preferred embodiment is equippedwith another antenna 316 for receiving communication from thecommunication network 319. These antennae (316, 318) in anotherpreferred embodiment are combined into a single antenna (not shown). Asone skilled in the art would appreciate, the antenna or antennae (316,318) in another embodiment are externally mounted on the device 300.

When equipped for two-way communication, the communication device 300features a communication subsystem 311. As is well known in the art,this communication subsystem 311 is modified so that it can support theoperational needs of the device 300. The subsystem 311 includes atransmitter 314 and receiver 312 including the associated antenna orantennae (316, 318) as described above, local oscillators (LOs) 313, anda processing module 320 which in a preferred embodiment is a digitalsignal processor (DSP) 320.

It is contemplated that communication by the device 300 with thewireless network 319 can be any type of communication that both thewireless network 319 and device 300 are enabled to transmit, receive andprocess. In general, these can be classified as voice and data. Voicecommunication is communication in which signals for audible sounds aretransmitted by the device 300 through the communication network 319.Data is all other types of communication that the device 300 is capableof performing within the constraints of the wireless network 319.

The user is capable of interacting with the device 300 through readinginformation displayed on the display screen 322, entering text using thekeyboard 332, and inputing cursor movement through the use of theauxiliary user input device 328, among other ways. The auxiliary userinput device 328 as described above is preferably a trackball 321, asdepicted in FIG. 9. Motion of the trackball 321 is assessed using aplurality of sensors 72, 74, 76, 78 that quantify rotational motion ofthe trackball 321 about an intersecting x-axis 82 and an intersectingy-axis 84 of the trackball (see FIG. 10).

In one embodiment, the plurality of sensors 72, 78 number two. One ofthe two sensors 72 outputs signals indicative of x-component rollingmotion of the trackball 321 relative to the handheld communicationdevice 300 and about the intersecting y-axis 84 of the trackball 321(see the rotational arrows about the y-axis in FIG. 10). The other ofthe two sensors 78 outputs signals indicative of y-component rollingmotion of the trackball 321 relative to the handheld communicationdevice 300 and about the intersecting x-axis 82 of the trackball 321(see the rotational arrows about the x-axis in FIG. 10). In thisconfiguration, the two sensors 72, 78 are oriented radially about thetrackball 321 with approximately ninety degree spacing therebetween. Inone embodiment, each of the sensors is a hall effect sensor locatedproximate the trackball.

In another embodiment, the plurality of sensors 72, 74, 76, 78 numberfour. A first pair of opposed sensors 72, 76 outputs signals indicativeof x-component rolling motion of the trackball 321 relative to thehandheld communication device 300 and about the intersecting y-axis 84.A second pair of opposed sensors 74, 78 outputs signals indicative of ay-component rolling motion of the trackball 321 relative to the handheldcommunication device 300 and about the intersecting x-axis 82. The foursensors 72, 74, 76, 78 are oriented radially about the trackball 321with approximately ninety degree spacing between consecutive sensors asdepicted in FIGS. 9 and 10.

Each produced x-direction signal represents a discrete amount ofx-component (incremental x-direction) rolling motion of the trackball321 relative to the handheld communication device 300 while eachproduced y-direction signal represents a discrete amount of y-component(incremental y-direction) rolling motion of the trackball 321 relativeto the handheld communication device 300.

The integration of the trackball assembly into handheld device 300 canbe seen in the exploded view of FIG. 11 showing some of the typicalcomponents found in the assembly of the handheld electronic device 300.The construction of the device benefits from various manufacturingsimplifications. The internal components are constructed on a single PCB(printed circuit board) 12. The keyboard 332 is constructed from asingle piece of material, and in a preferred embodiment is made fromplastic. The keyboard 332 sits over dome switches (not shown) located onthe PCB 12 in a preferred embodiment. One switch is provided for everykey on the keyboard in the preferred embodiment, but in otherembodiments more than one switch or less than one switch per key arepossible configurations. The support frame 11 holds the keyboard 332 andnavigation tool 328 in place above the PCB 12. The support frame 11 alsoprovides an attachment point for the display (not shown). A lens 13covers the display to prevent damage. When assembled, the support frame11 and the PCB 12 are fixably attached to each other and the display ispositioned between the PCB 12 and support frame 11.

The navigation tool 328 is frictionally engaged with the support frame11, but in a preferred embodiment the navigation tool 328 is removablewhen the device is assembled. This allows for replacement of thenavigation tool 328 if/when it becomes damaged or the user desiresreplacement with a different type of navigation tool 328. In theexemplary embodiment of FIG. 11, the navigation tool 328 is a ball 321based device. Other navigation tools 328 such as joysticks, four-waycursors, or touch pads are also considered to be within the scope ofthis disclosure. When the navigation tool 328 has a ball 321, the ball321 itself can be removed without removal of the navigation tool 328.The removal of the ball 321 is enabled through the use of an outerremovable ring 23 and an inner removable ring 22. These rings 22, 23ensure that the navigation tool 328 and the ball 321 are properly heldin place against the support frame 11.

A serial port (preferably a Universal Serial Bus port) 330 and anearphone jack 40 are fixably attached to the PCB 12 and further held inplace by right side element 15. Buttons 30-33 are attached to switches(not shown), which are connected to the PCB 12.

Final assembly involves placing the top piece 17 and bottom piece 18 incontact with support frame 11. Furthermore, the assembly interconnectsright side element 15 and left side element 16 with the support frame11, PCB 12, and lens 13. These side elements 16, 15 provide additionalprotection and strength to the support structure of the device 300. In apreferred embodiment, backplate 14 is removably attached to the otherelements of the device.

As intimated hereinabove, one of the more important aspects of thehandheld electronic device 300 to which this disclosure is directed isits size. While some users will grasp the device 300 in both hands, itis intended that a predominance of users will cradle the device 300 inone hand in such a manner that input and control over the device 300 canbe affected using the thumb of the same hand in which the device 300 isheld, however it is appreciated that additional control can be effectedby using both hands. As a handheld device 300 that is easy to grasp anddesirably pocketable, the size of the device 300 must be kept relativelysmall. Of the device's dimensions, limiting its width is important forthe purpose of assuring cradleability in a user's hand. Moreover, it ispreferred that the width of the device 300 be maintained at less thanten centimeters (approximately four inches). Keeping the device 300within these dimensional limits provides a hand cradleable unit thatusers prefer for its usability and portability. Limitations with respectto the height (length) of the device 300 are less stringent whenconsidering hand-cradleability. Therefore, in order to gain greatersize, the device 300 can be advantageously configured so that its heightis greater than its width, but still remain easily supported andoperated in one hand.

A potential problem is presented by the small size of the device 300 inthat there is limited exterior surface area for the inclusion of userinput and device output features. This is especially true for the “primereal estate” on the front face of the device 300, where it is mostadvantageous to include a display screen 322 that outputs information tothe user. The display screen 322 is preferably located above a keyboardthat is utilized for data entry into the device 300 by the user. If thescreen 322 is provided below the keyboard 332, a problem occurs in thatviewing the screen 322 is inhibited when the user is inputting datausing the keyboard 332. Therefore it is preferred that the displayscreen 322 be above the input area, thereby solving the problem byassuring that the hands and fingers do not block the view of the screen332 during data entry periods.

To facilitate textual data entry into the device 300, an alphabetickeyboard is provided. In one version, a full alphabetic keyboard 332 isutilized in which there is one key per letter. In this regard, theassociated letters can be advantageously organized in QWERTY, QWERTZ,AZERTY or Dvorak layouts, among others, thereby capitalizing on certainusers' familiarity with these special letter orders. In order to staywithin the bounds of the limited front surface area, however, each ofthe keys must be commensurately small when, for example, twenty-six keysmust be provided in the instance of the English language.

An alternative configuration is to provide a reduced keyboard in whichat least some of the keys have more than one letter associated therewith(see FIG. 1 for an example). This means that fewer keys are requiredwhich makes it possible for those fewer keys to each be larger than inthe instance when a full keyboard is provided on a similarly dimensioneddevice. Some users will prefer the solution of the larger keys over thesmaller ones, but it is necessary that software or hardware solutions beprovided in order to discriminate which of the several associatedletters the user intends based on a particular key actuation, a problemthe full keyboard avoids.

Preferably, the character discrimination is accomplished utilizingdisambiguation software included on the device 300. To accommodatesoftware use on the device 300, a memory 324 and microprocessor 338 areprovided within the body of the handheld unit for receiving, storing,processing, and outputting data during use. Therefore, the problem ofneeding a textual data input means is solved by the provision of eithera full or reduced alphabetic keyboard 332 on the presently disclosedhandheld electronic device 300. It should be further appreciated thatthe keyboard 332 can be alternatively provided on a touch sensitivescreen in either a reduced or full format.

Keys, typically of a push-button or touchpad nature, perform well asdata entry devices but present problems to the user when they must alsobe used to affect navigational control over a screen-cursor. In order tosolve this problem, the present handheld electronic device 300preferably includes an auxiliary input that acts as a cursornavigational tool and which is also exteriorly located upon the frontface of the device 300. Its front face location is particularlyadvantageous because it makes the tool easily thumb-actuable like thekeys of the keyboard. In a particularly useful embodiment, thenavigational tool is a trackball 321 which is easily utilized toinstruct two-dimensional screen cursor movement in substantially anydirection, as well as act as an actuator when the ball of the trackball321 is depressed like a button. The placement of the trackball 321 ispreferably above the keyboard 332 and below the display screen 322;here, it avoids interference during keyboarding and does not block theuser's view of the display screen 322 during use (See FIG. 1).

In some configurations, the handheld electronic device 300 may bestandalone in that it does not connect to the “outside world.” Asdiscussed before, one example would be a PDA that stores such things ascalendars and contact information but is not capable of synchronizing orcommunicating with other devices. In most situations such isolation willbe viewed detrimentally in that synchronization is a highly desiredcharacteristic of handheld devices today. Moreover, the utility of thedevice 300 is significantly enhanced when connectable within acommunication system, and particularly when connectable on a wirelessbasis in a network 319 in which voice, text messaging, and other datatransfer are accommodated.

As shown in FIG. 1, the handheld electronic device 300 is cradleable inthe palm of a user's hand. The handheld device 300 is provided with akeyboard 332 to enter text data and place telephone calls and a displayscreen 322 for communicating information to the user. A connect/send key605 is preferably provided to aid in the placement of a phone call.Additionally, a disconnect/end key 609 is provided. The send key 605 andend key 609 preferably are arranged in a row of keys including aauxiliary input device 328. Additionally, the row of keys, including thenavigation tool, preferably has a menu key 606 and a back key or escapekey 608. The menu key 606 is used to bring up a menu and the escape key608 is used to return to the previous screen or previous menu selection.

The handheld electronic device 300 includes an input portion 604 and anoutput display portion. The output display portion can be a displayscreen 322, such as an LCD or other similar display device.

The keyboard 332 includes a plurality of keys that can be of a physicalnature such as actuable buttons or they can be of a software nature,typically constituted by virtual representations of physical keys on adisplay screen 322 (referred to herein as “software keys”). It is alsocontemplated that the user input can be provided as a combination of thetwo types of keys. Each key of the plurality of keys has at least oneactuable action which can be the input of a character, a command or afunction. In this context, “characters” are contemplated to exemplarilyinclude alphabetic letters, language symbols, numbers, punctuation,insignias, icons, pictures, and even a blank space. Input commands andfunctions can include such things as delete, backspace, moving a cursorup, down, left or right, initiating an arithmetic function or command,initiating a command or function specific to an application program orfeature in use, initiating a command or function programmed by the userand other such commands and functions that are well known to thosepersons skilled in the art. Specific keys or other types of inputdevices can be used to navigate through the various applications andfeatures thereof Further, depending on the application 358 or feature inuse, specific keys can be enabled or disabled.

In the case of physical keys, all or a portion of the plurality of keyshave one or more indicia, representing character(s), command(s), and/orfunctions(s), displayed at their top surface and/or on the surface ofthe area adjacent the respective key. In the instance where the indiciaof a key's function is provided adjacent the key, the indicia can beprinted on the device cover beside the key, or in the instance of keyslocated adjacent the display screen 322. Additionally, current indiciafor the key may be temporarily shown nearby the key on the screen 322.

In the case of software keys, the indicia for the respective keys areshown on the display screen 322, which in one embodiment is enabled bytouching the display screen 322, for example, with a stylus to generatethe character or activate the indicated command or function. Someexamples of display screens 322 capable of detecting a touch includeresistive, capacitive, projected capacitive, infrared and surfaceacoustic wave (SAW) touchscreens.

Physical and software keys can be combined in many different ways asappreciated by those skilled in the art. In one embodiment, physical andsoftware keys are combined such that the plurality of enabled keys for aparticular application or feature of the handheld electronic device 300is shown on the display screen 322 in the same configuration as thephysical keys. Using this configuration, the user can select theappropriate physical key corresponding to what is shown on the displayscreen 322. Thus, the desired character, command or function is obtainedby depressing the physical key corresponding to the character, commandor function displayed at a corresponding position on the display screen322, rather than touching the display screen 322.

The various characters, commands and functions associated with keyboardtyping in general are traditionally arranged using various conventions.The most common of these in the United States, for instance, is theQWERTY keyboard layout. Others include the QWERTZ, AZERTY, and Dvorakkeyboard configurations. The QWERTY keyboard layout is the standardEnglish-language alphabetic key arrangement 44 a shown in FIG. 5 a. TheQWERTZ keyboard layout is normally used in German-speaking regions; thisalphabetic key arrangement 44 b is shown in FIG. 5 b. The AZERTYkeyboard layout 44 c is normally used in French-speaking regions and isshown in FIG. 5 c. The Dvorak keyboard layout was designed to allowtypists to type faster; this alphabetic key arrangement 44 d is shown inFIG. 5 d.

Alphabetic key arrangements are often presented along with numeric keyarrangements. Typically, the numbers 1-9 and 0 are positioned in the rowabove the alphabetic keys 44 a-d, as shown in FIG. 5 a-d. Alternatively,the numbers share keys with the alphabetic characters, such as the toprow of the QWERTY keyboard. Yet another exemplary numeric keyarrangement is shown in FIG. 6, where a “ten-key” style numeric keypad46 is provided on a separate set of keys that is spaced from thealphabetic/numeric key arrangement 44. The ten-key styled numeric keypad46 includes the numbers “7”, “8”, “9” arranged in a top row, “4”, “5”,“6” arranged in a second row, “1”, “2”, “3” arranged in a third row, and“0” in a bottom row. Further, a numeric phone key arrangement 42 isexemplarily illustrated in FIG. 7.

As shown in FIG. 7, the numeric phone key arrangement 42 may alsoutilize a surface treatment on the surface of the center “5” key. Thissurface treatment is configured such that the top surface of the key isdistinctive from the surface of other keys. Preferably the surfacetreatment is in the form of a raised bump or recessed dimple 43.Alternatively, raised bumps may be positioned on the housing around the“5” key and do not necessarily have to be positioned directly on thekey.

It is desirable for handheld electronic devices 300 to include acombined text-entry keyboard and a telephony keyboard. Examples of suchmobile communication devices 300 include mobile stations, cellulartelephones, wireless personal digital assistants (PDAs), two-way pagingdevices, and others. Various keyboards are used with such devices andcan be termed a full keyboard, a reduced keyboard, or phone key pad.

In embodiments of a handheld electronic device 300 having a fullkeyboard, the alphabetic characters are singly associated with theplurality of physical keys. Thus, in an English-language keyboard ofthis configuration, there are at least 26 keys in the plurality so thatthere is at least one key for each letter.

FIGS. 7 and 8 both feature numeric keys arranged according to the ITUStandard E.161 form. In addition, FIG. 8 also incorporates alphabeticcharacters according to the ITU Standard E. 161 layout as well.

As intimated above, in order to further reduce the size of a handheldelectronic device 300 without making the physical keys or software keystoo small, some handheld electronic devices 300 use a reduced keyboard,where more than one character/command/function is associated with eachof at least a portion of the plurality of keys. This results in certainkeys being ambiguous since more than one character is represented by orassociated with the key, even though only one of those characters istypically intended by the user when activating the key.

Thus, certain software usually runs on the processor 338 of these typesof handheld electronic devices 300 to determine or predict what letteror word has been intended by the user. Some examples of software includepredictive text routines which typically include a disambiguation engineand/or predictive editor application. The software preferably also hasthe ability to recognize character letter sequences that are common tothe particular language, such as, in the case of English, words endingin “ing.” Such systems can also “learn” the typing style of the usermaking note of frequently used words to increase the predictive aspectof the software. Other types of predictive text computer programs may beutilized with the reduced keyboard arrangements described herein,without limitation. Some specific examples include the multi-tap methodof character selection and “text on nine keys”.

The keys of reduced keyboards are laid out with various arrangements ofcharacters, commands and functions associated therewith. In regards toalphabetic characters, the different keyboard layouts identified aboveare selectively used based on a user's preference and familiarity; forexample, the QWERTY keyboard layout is most often used by Englishspeakers who have become accustomed to the key arrangement.

FIG. 1 shows a handheld electronic device 300 that carries an example ofa reduced keyboard using the QWERTY keyboard layout on a physicalkeyboard array of twenty keys comprising five columns and four rows.Fourteen keys are used for alphabetic characters and ten keys are usedfor numbers. Nine of the ten numbers share a key with alphabeticcharacters. The “space” key and the number “0” share the same key, whichis centered on the device and centered below the remainder of thenumbers on the keyboard 332. While in other embodiments, the number “0”may be located on other keys. Many of the keys have different sizes thanthe other keys, and the rows are non-linear. In particular, the keys inthe middle column 64 are wider than keys in the outer columns 60, 62, 66and 68. To readily identify the phone user interface (the second userinterface), the numeric phone keys 0-9 include a color scheme that isdifferent from that of the remaining keys associated with the QWERTY keyarrangement. As exemplified in FIG. 1, a color scheme of the numericphone keys has a two tone appearance, with the upper portion of thenumeric keys being a first color and the lower portion of the numerickeys being a second color. The first color may be lighter than thesecond color, or darker than the second color.

Another embodiment of a reduced alphabetic keyboard is found on astandard phone keypad 42. Most handheld electronic devices 300 having aphone key pad 42 also typically include alphabetic key arrangementsoverlaying or coinciding with the numeric keys as shown in FIG. 8. Suchalphanumeric phone keypads are used in many, if not most, traditionalhandheld telephony mobile communication devices such as cellularhandsets.

As described above, the International Telecommunications Union (“ITU”)has established phone standards for the arrangement of alphanumerickeys. The standard phone numeric key arrangement shown in FIGS. 7 (noalphabetic letters) and 8 (with alphabetic letters) corresponds to ITUStandard E.161, entitled “Arrangement of Digits, Letters, and Symbols onTelephones and Other Devices That Can Be Used for Gaining Access to aTelephone Network.” This standard is also known as ANSI TI.703-1995/1999and ISO/IEC 9995-8:1994. Regarding the numeric arrangement, it can beaptly described as a top-to-bottom ascending orderthree-by-three-over-zero pattern.

While several keyboard layouts have been described above, alternativelayouts integrating the navigation tool into the keyboard are presentedbelow. The key arrangements and mobile devices described herein areexamples of a conveniently sized multidirectional navigational input keythat is integrated with an alphanumeric key layout. The examplemultidirectional navigational input keys can be used in a navigationmode to move, for example, a cursor or a scroll bar. In an alphabetic ornumeric mode, it can be used to enter numbers or letters. This dualfeature allows for fewer and larger keys to be disposed on the keyboardwhile providing for a QWERTY, reduced QWERTY, QWERTZ, Dvorak, or AZERTYkey layout and navigational input. These familiar keyboard layouts allowusers to type more intuitively and quickly than, for example, on thestandard alphabetic layout on a telephone pad. By utilizing fewer keys,the keys can be made larger and therefore more convenient to the user.

In some examples, keys in the middle columns are larger than keys in theouter columns to prevent finger overlap on the interior keys. As usedherein, middle columns are all columns that are not on the outside leftand right sides. The term “middle column” is not limited to the centercolumn. It is easier for a user to press keys on the outer columnswithout their finger overlapping an adjacent key. This is because partof the user's thumb or finger can overlap the outside housing of thedevice, rather than other keys. Therefore, these outer column keys canbe made smaller. The multidirectional navigational input device isprovided in the center of the keypad and has a larger surface than theoutside keys. The larger surface in the inner part of the keyboard helpsprevent finger overlap.

Exemplary embodiments have been described hereinabove regarding bothhandheld electronic devices 300, as well as the communication networks319 within which they cooperate. Again, it should be appreciated thatthe focus of the present disclosure is ability to remove the trackballand/or trackball assembly from an assembled handheld electronic device.

1. A handheld wireless communication device configured to send andreceive text messages, said device comprising: a hand cradleable bodyconfigured to be held in one hand by an user of said device during textentry; a display located on a front face of said body and upon whichinformation is displayed to the user during text entry; a key fieldlocated on the front face of said body, said key field being composed ofa plurality of alphanumeric input keys and menu control keys; and anuser-removable trackball navigation tool, said trackball navigation toolbeing one of releasably snap-engaged and releasably friction-engaged insaid hand cradleable body thereby enabling the user of the handheldwireless communication device to independently remove the trackballnavigation tool from the device and perform self-maintenance on thedevice with respect to the navigation tool.
 2. The handheld wirelesscommunication device as recited in claim 1, wherein said trackballnavigation tool is releasably snap-engaged in said hand cradleable body.3. The handheld wireless communication device as recited in claim 2,wherein said trackball navigation tool comprises a freely rotatable balland a sensor assembly that detects rotation of the ball.
 4. The handheldwireless communication device as recited in claim 3, wherein the ball isretained in a fixed position relative to the sensor assembly by a ballretaining clip.
 5. The handheld wireless communication device as recitedin claim 4, wherein said ball retaining clip comprises a ball retainingring and a plurality of fixing feet extending from said ball retainingring.
 6. The handheld wireless communication device as recited in claim5, wherein each of said plurality of fixing feet extends in a directionparallel to a longitudinal axis of the trackball navigation tool.
 7. Thehandheld wireless communication device as recited in claim 6, whereinsaid trackball navigation tool is mounted within a cavity at the frontface of the body.
 8. The handheld wireless communication device asrecited in claim 7, further comprising a trackball assembly retainingclip releasably retaining the trackball assembly in the cavity at thefront face of the body.
 9. The handheld wireless communication device asrecited in claim 8, wherein said trackball assembly retaining clipcomprises a trackball assembly retaining ring and a plurality ofsnap-engaging feet extending from said trackball assembly retainingring.
 10. The handheld wireless communication device as recited in claim9, wherein each of said plurality of snap-engaging feet extends in adirection parallel to the longitudinal axis of the trackball navigationtool.
 11. The handheld wireless communication device as recited in claim10, wherein each of said plurality of snap-engaging feet releasablyengages a lateral port in said cavity at the front face of the body. 12.The handheld wireless communication device as recited in claim 11,wherein each of said plurality of snap-engaging feet includes aninclined surface for snap-engagement with a complimentary inclinedsurface in a respective lateral port in said cavity at the front face ofthe body.
 13. The handheld wireless communication device as recited inclaim 1, wherein said alphanumeric input keys comprising a plurality ofalphabetic keys having letters associated therewith.
 14. The handheldwireless communication device as recited in claim 13, wherein saidletters associated with said alphanumeric keys are arranged in a QWERTYlayout.
 15. The handheld wireless communication device as recited inclaim 13, wherein said letters associated with said alphanumeric keysare arranged in a reduced-QWERTY layout.
 16. The handheld wirelesscommunication device as recited in claim 13, wherein said lettersassociated with said alphanumeric keys are arranged in a QWERTZ layout.17. The handheld wireless communication device as recited in claim 1,wherein said alphanumeric input keys comprise numeric keys havingnumerals associated therewith and wherein said associated numerals arearranged in a telephone keypad layout.
 18. The handheld wirelesscommunication device as recited in claim 1, wherein said body isconfigured to be held in the hand of the user with a long axis of saiddevice substantially horizontally oriented during text entry.
 19. Thehandheld wireless communication device as recited in claim 1, whereinsaid body is configured to be held in the hand of the user with a longaxis of said device substantially vertically oriented during text entry.20. The handheld wireless communication device as recited in claim 1,wherein said display is located in an upper portion of the front face ofsaid body during text entry, said key field is located in a lowerportion of the front face of said body during text entry and saidtrackball is located substantially between said key field and saiddisplay.
 21. The handheld wireless communication device as recited inclaim 1, wherein said trackball navigation tool is at least partiallysurrounded by said key field.